Originally Posted by 5.8GT
I think you have the wrong plugs, your car should take a ar25. Like Trojan said check them next to the plugs you take out. The ar3932 looks like it has a gasket seat and you car should have a tapered seat.
Good point. I never looked them up.
The 95 I owned previously had exactly that issue when I first got it.
They used the gasketed plugs on heads that were machined for tapered seats.
It ran a good bit better with the proper plugs.